Currently, testing to determine gate oxide process-induced damage on semiconductor devices has been performed by supplying a test current or voltage ramp to the gate oxide until gate oxide breakdown. This method works well for devices with gate oxides having a thickness of 100 .ANG. or more. However, incorrect breakdown current, voltage, and/or charge information are often provided by this method due to the different gate oxide current vs. voltage characteristics of devices with thin gate oxides less than 100 .ANG. thick. In thin gate oxide devices, the tunneling current becomes a much more dominant component of the current flowing through the gate oxide during a current or voltage ramp test. This alters the breakdown characteristics of the device and may lead to incorrect conclusions on the integrity of the gate oxide in these devices.
Accordingly, there is a need for a test method to determine thin gate oxide integrity of semiconductor devices to detect plasma damage and other process-induced damage effects that may lead to abnormally high breakdown voltages, series resistance, early breakdown, early leakage, and self healing phenomena.